Telephone receiver



Aug. 4, 1925. 1,548,325

H. KOCH TELEPHONE RECEIVER Filed Jung 28, 1922 Zyl mvamtoz vPatented Aeg. 4, 1925.

- Unirse STATI-:s .P la'raN"11A OFFICE'.

HENRY xooruor Jamaica, NEW Yonx. Assrenon 'ro nrcroenarn PRODUCTS conF i POBLATIONQAA' CORPORATION' OF -TELEPHQNE nncmvnn. v L

Application mea :une 2s, ma. serial no. 571507.

To qll 'whom it may concentra: Beit-known that I. HENRY KOCH, a cit-'i- Vzen of the United States, residing at J a'- maica, in the county of Queens andkl State vof NevWYork, vhave invented certain neu7 anduseful Improvements in Telephone Receivers, of which 'the following iis a full, clear, and exact description.

`This inventlon relates to` telephone receivers, in which undulations or alternations of electric current are converted into sound Waves. An object 'of the invention is to provide an (improved receiver of this tvpe in which the. external circuit connections are made within the casing and which is exceedinglxv light, simplef` compact; durable,

and inexpensivein construction, and eicient in operation. A further object is to provide a receiver of this tvpe` in which the binding 'L posts or circuitvterminals'of vthe receiver ,will

be relieved ofpulling stresses upon thefex-l ternal circuit cable or Wires-.land in which the internal. mechanism will. in -a simple` and effective manner, be held against rotationin the casing. Orther objects and-advantages willbe apparent from the follow'- vention. andthe novel featureswill e par- In the accompanying drawing: p 1 Fig. 1 is a sectional elevation of a receiver constructed in accordance withv this invention: c

Fig.' Q'is another sectional elevation of the same: y

- Fig. 3 is an elevation of the internal mechanism,reniovefvlfrom thecasing;

Fig.4. is a' sectional elevation of aportion ,of the receiver; .4 I- Y e" lig. 5.is Aan elevation of certain` details; Fig. 6 lis a plan ,of a portion of the exttrnal circuit cable, showing the anchoringA cor f l J In the illustrated embodiment, a: casing `1 of suitable light material such as .alumi-4 across theI casing, and is Vprovided with al peripherallyextending ange 4 which overal hes the Aopen vedge of thecasing and .is

phragmL The endsl 11 terminate in close c lamped`between the same and the ear piece cap 2., A diaphragm 5 isclamped against and' across the peripheral flange 4 of the\` frame by the ear piece cap 2.` A plurality` of permanent magnets 6 somewliat circular 60 in shape are disposed face to face and flat .against one face of the frame 3, with theirV corresponding polar ends aligned with one another. Polar' extensions 7 are disposed" Afiat against the polar ends of the permanent magnets 6, and bolts or screws 8 pass through the polar extensions 7 the polar ends of the magnets 6, and the bottom wall of the frame 3. and are in threaded engagement with nuts '9 that aret held against rotation -within Lpockets 10 in the face ofthe |`frame opposite from .the' magnets. `When the bolts 8.are tightened, the olar extensions Vwill be firm- 1 v clamped to lhe polar ends of the permanent maq'nets and both will be firmly clamped to 'theframe 3. The opposite polar ends of the permanent magnets are spaced apart a short distance andthe polar extensions extend substantially radially ofV the 'casing into the central portion thereof and have angular ends 11 which extend parallel to ing description of an embodiment o. the ins one another through a central aperture 3 of the `franand perpendicular to thevdiaproximityto but 'slightly spaced from the 85 diaphragm. as usual in telephone receivers. Ain electromagnet coil 1 2 is disposed upon the angular end 11 of each polar extension, so as to modify the magnetic ux passing therethrough with variatlons in the current passing through-the coil, and these coils 12 are connected together in series by a Wire 13.

Binding`posts 14 are provided with reduced .extensions 15 which pass,` through spaced apertures 16in a pla-te 17 of insulatying material and each reduced extension also passes through an aperture n1 a'conductmg strip 18 and a washer 19, the projecting ends i of the' reduced extensions being enlarged or upset, suchI as b v peening, to -firmly rlvet a AWasher and conducting strip to each bind- "ing post, and bot-h binding posts wlth thelil c aul plate 22 is disposed flat against the plate 20 to insulate the reduced ends of the binding posts. The plates 17, 20 and 22 are placed in superposed relation up on the frame 3 between the spaced polar ends of the 'permanent magnet with the binding posts 11i extending upwardly or away from the frame 3. Bolts23 pass through the frame 3,the insulating plates 17, 20 and 22 and cooperate with nuts 24 to securely clamp these parts and the binding posts to the frame. The conducting strips 18 extend toward the electromagnet coils, terminatingin close proximity thereto, and the circuitends of the coils of the electromagnets are soldered or" otherwise suitably secured thereto to form e ectrical connections between the coils and the binding posts. The insulating plates 17, 2O and 22 serve to insulate the binding posts.

and conducting strips from one another and from the frame 3. The binding posts are each provided with a transverse aperture-25 in which a terminal 26 of an external cir` cuit wire 27 may be detachably clamped by a set screwu 28. The wires 27pass into the casing through apertures 29 therein, and exteriorly of the casing are united lnto a common twin wire cable 30. -v

`A pin like member 31 having a head 32 rintermediate of its length extends through the permanent magnets at points intermediate their ends, and through the frame 3, into threaded engagementwith a nut .33for clamping the permanent A magnets to the frame 3. A spacing washer 34 may, if desired, be disposed between? the permanent magnets and the frame 3, 'and through which the member 31 may pass.. The nut 33 is countersunk into a pocket 35-in a face of the frame 3 so as to be held against rotation with the member 31. The other end of the member 31 extends into or through an aperture 36 in thesbaclr wall of the casing 1 which prevents rotation of the frame and parts ca'rried thereby within the casing. y,An anchoring cord 37 isconnected to\or formed as part of the twin wire cable 30 of the external circuit, passes through an aperture 38 in the casing, varound an annular groove 39 in the member 31', and leaves the casing through the aperture 38. Theextending free end of the cord is then tied or otherwise anchored to the cable 30, or the component wires 27 thereof, so that any pulling forces upon the cable or external circuit wires will be resisted by the anchoring cord and member 31, whichorelieveslthe binding posts of the pulling'forces. The member..31 therefore serves the triple` function of clamping the permanent magnets to the frame 3, preventing'rotation of the internal mechanism withinthe casing and serving as an anchoring mediumfor the anchorin cord 37'. v The casing' may be-provided with diametrically disposed depression 40 in its peiriphery by means of which the receiver casing may be pivotally mounted between the forked resilient arms carried at an end of a head band (not shown).

- When access to the interior ofthe casing is desired, the ear piece 'cap 2 is unscrewed andthe anchoring cord 37 is untied or loosened. The diaphragm may be removed and the frame 3 pulled outwardly. This provides access to the binding posts 14 so that the circuit wires 27 may be connected thereto or` disconnected therefrom. The f parts may be replaced within the casing in a reverse order, after whichthe cord 37 may be tightened, and tied or otherwise secured to the cable 30 so as to relieve the binding 1. In' a telephone receiver, a casing, sound producing mechanism within the casing and having terminal binding. posts, clrcuit wires entering the casing and connected tosaid binding posts; a pin carried by said mechanism and coacting with the casinglto .prevent rotation of the mechanism therein, an anchoring cord connected to said wires and anchored to said pin within the casing to transfer pulling stresses upon the wires directly to said .pin and relieve'the binding posts of the same. I

2. In atelephone receiver, a casing having an aperture, sound producing mechanism within the casing and having circuit ter tminals, circuit conductors entering the casing and connected t/o said circuit` terminals,

a pin carried by the'mechanism and enterlngbthe aperture in the casing to prevent ro tatlon of the mechanism in the casing, an

anchoring cord connected to the cable and i anchored to said pin .within the casing to re- `lieve the connections between lthe icircuit conductors and the circuit ,terminals vof thel pulling stresses upon the conductors.

3. In a telephone receiver, a-casing having an aperture in its bottom wall, a removable apertured cap threaded over the open end ofy the casing, a frame disposed in the casing Vand having a central' aperture and a flangel overlying the open edge of the casing, a diaphragm extending across theframe, said diaphragm and frame being clamped across the open edge of the casing'by the cap, a I,permanent magnet disposed flat against the frame, pole pieces disposed flat against the -magnet poles` and extendinginto'the central s portion of the casing, the inner ends of the pole pieces extending Aparallel to oneI another and perpendicularly toward the diaphragm, terminating in close proximity thereto,l screws passing through the polepieces andmagnet ends and cooperating with the frame to secure the pole pieces to the peri manent magnet and both to the frame, electromagnet coil windings on the free parallel end portions of the pole pieces, binding posts disposed in the .space between the ends of vaperture cap threaded over the open end of m the casing, a frame disposed in the casing and having a central aperture and a viange `overlying the opengedge of the casing, a

diaphragm extending acrossy the frame. said diaphragm and frame being clamped across the open edge of the casingk by the cap. a permanent magnet disposed iiat. against the frame, pole pieces disposed flat against the magnet poles and extending into the central portion o the casing, -the inner ends of the pole pieces extending parallel to one another and perpendicularly toward the diaphragm, terminating in close proxiinityv thereto` screws passing through the pole pieces and magnet ends and cooperating with theframe to secure the pole pieces to the permanent magnet vand both to the'rame, electromag 'l net ,coil windings on t-he free vparallel end portions of the pole pieces,`bindingI posts disposedl in the space between the ends of. the permanent magnetrand to which external circuit wires may befconnected, means con- 1necting the binding posts to the coil windings,- and a member engaging the permanent with lthe casin magnet at a pointintermediate of its poles and clampin the same to the frame,v said member having an extension rlcooperating to prevent rotation of the frame within t e casing. t 1 t 5./.In a telephone recelver, a' casing having an aperture in its bottom wall, a` removable aperture cap threaded over the open end of thecasing, a frame disposed in the casing and having a central aperture and a flange overlying the open edge -of the casing, a diaphragm extendingacrossthe frame, said diaphragm. and framebeing clamped across the open edge of the casing by the cap, a permanent magnet disposed Hat against the frame, pole pieces disposed flat. against the magnet poles and extending into the central 'portion of the casing, the inner ends of the pole pieces extending parallel to one another and perpendicularlv toward the diaphragm.

"I y terminating I in close proximity thereto,V y

screws passing through the pole pieces and necting the binding posts to the coil windings, a. member engaging the permanent magnet ata point intermediate of its poles and clamping the same to theframe. said member having an extension cooperating with the casing to prevent rotation of the frame within the casing, and an anchoring cord connected to the circuit wires and said member to relieve the binding posts of pulling forces upon the circuit wires. 6. In a telephone receiver, a casing having an aperture in its bottom wall, a removable apertured cap threaded over the K open end of the casing, a frame disposed inthe casing and having a central aperture and a flange overlying the open edge of the casing, a diaphragm extending across the fra-me, said diaphragm and frame being cl-amped across the open edge of the casing by the ca a permanent magnet disposed iiat agains the frame, pole pieces disposed :fiat against the magnet poles and extending 945 v into the central portioniof the casing, the inner ends of the pole pieces extending parallel to one another and perpendicularly toward the diaphragm, terminating in c lose` proximity thereto, screws passing through the Vpole pieces and magnet ends and cooperating with the frame to secureathe pole` pieces to the permanent magnet and both to the frame, electromagnet coil windings on the free parallel end portions ofthe pole pieces, binding posts dispose/d in the space between the ends, of the permanent magnet` external circuit wires connected to said binding posts, means connecting the bind-l ing posts tothe coil windings,f and means 110" extending into the casing for anchoring the circuit wlres to relieve the binding posts of pulling forces upon the circuit wires.

7. In a telephone receiver, a casing hav ing an aperture in its bottom wall, a remov. 115- able apertured cap threaded over the open end of the casing, a frame disposed in the casing and having a central aperture and a flange overlying the open' edge of" the casing, a ,diaphragm extending across `the 1.20 frame, said diaphragm and frame being clamped across the open edge of the easing `byk the cap, a permanent magnet disposed Hat against the frame, pole pieces disposed flat against the magnet poles and extending into the central portion of the casing, the inner ends of the pole pieces extending paralleltoone another and perpendicularly toward the diaphragm. terminating in close proximity thereto, screws passing through the pole pieces and magnet ends and cooperating with vthe frame to secure the pole pieces to the permanent magnet and both to the frame. elcctromagnet coil windings on the free parallel end vportions of the pole pieces, binding posts disposed in the space between the ends of the permanent magnet, external circuit wires entering the casing and connected to said binding posts, means for connecting the binding posts to the coil windings, a member carried by the 'frame and cooperating with the casing to prevent rotation of the frame therein, and an anchoring device connected to the member and to the external circuit Wires for relieving the binding posts of pulling forces upon the external circuit wires.

8. In a telephone receiver, a casing, mechanism within the casing for converting variations in current into sound waves said mechanism including a frame and a permanent magnet, circuit binding posts for said mechanism within the casing, external circuit Wires entering the casing and connect-VL ed to said binding posts, a cord connected to said circuit Wires, a member engaging the permanent magnet and cl-amping the same to the frame, and an anchoring cord connected to the circuit wires and said member to relieve the binding posts of pulling forcesupon the said circuit wires.

9. In a telephone receiver, a casing having an aperture in its bottom wall, a re"\ movable apertured cap threaded over the open end of che casing, a frame disposed in the casing and having a central aperallel to one another and perpendicularly toward the diaphragm, terminating in close proximity thereto, means for securing the magnet with its pole piecesto said frame, circuit binding posts disposed in the space betweenthe polar ends of the permanent magnet and external circuit `wires connected to said binding posts.

l0. In a telephone receiver, a casing, a frame in the casing, a permanent magnet carried by the frame, and having spaced polar ends, an apertured insulating plate, a plurality of binding posts each having a reduced extension passing through an aperture of the plate, a conducting strip riveted `upon each extension, a secondV insulating plate in the space between the polar ends and between the irst plate and the frame, means for clamping said insulating plates together and to ther frame, polar extensions carriedby the polar ends of the permanent magnet, and coils carried by the polar extensions and connected to said conducting strips. i'

Inwitness whereof, I hereunto subscribe my signature.

' HENRY KOCH. 

